1. Field of the Invention
The invention relates in general to voltage control and in particular to digital voltage control for high frequency voltage regulators.
2. Statement of the Problem
Analog voltage controllers are widely used in cooperation with power converters for DC-DC (direct-current to direct-current) converters. Analog controllers are fast and can generally be built with widely available analog components. However, the operation of analog controllers depends on the precision of the individual components included therein. Accordingly, considerable effort must be expended to ensure selection of analog components adhering to very precise quality control standards. Moreover, even after such careful selection, the behavior of analog components is subject to variations in manufacturing processes, operating temperatures, and degradation over time. Moreover, analog designs are not readily realized employing existing automated design methods. Accordingly, the design of analog controllers tends to be time-consuming and labor intensive.
Some existing voltage controllers include one or more digitally implemented components. However, the digital components implemented in existing voltage controllers have not performed as desired. For example, digital signal processors (DSPs) have been implemented to perform arithmetic operations, such as multiplication, as part of the operation of a compensator, within a voltage controller. However, these DSP implementations are slow, take up a lot of space, and are excessively complex for the task being performed. Moreover, because the DSPs require digital data to operate, their implementation incurs the need for large and energy-expensive analog to digital converters (ADCs). The ADCs included in such controllers are precision analog components which take up an inordinate amount of valuable space on chips, consume large amounts of power, and are subject to the same temperature-induced and process-induced performance variations as are analog components of the older existing controllers.
Accordingly, the art of voltage control would benefit from the provision of a voltage controller which is small, energy and space-efficient, and whose performance is not dependent of the temperature and process variations of individual controller components.